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SHRI Video Training Series2018 dx and forwardRecorded 1/2020

1Colorectal Introduction & Anatomy

Presented by Lori Somers, RNIowa Cancer Registry

2020

GI Tract Anatomy

Liver

StomachGallbladder

Pancreas

SmallIntestine

Esophagus

Diaphragm

Pharynx

Anal Canal

LargeIntestine(COLON)

Mouth

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Colorectal AnatomyPrimary Site ICD-O Codes for Colon and Rectum

TransverseC18.4

Sigmoid C18.7

Descending C18.6

Rectosigmoid C19.9Rectum C20.9

Ascending C18.2

Cecum C18.0

Splen. FlexC18.5

Hep. FlexC18.3

Appendix C18.1

Large Intestine, NOS C18.9

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ILEOCECAL JUNCTION

Ileocecalsphincter

ILEUM

APPENDIXOpening of appendix 4

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Rectum, Rectosigmoid and Anus

Anus

Anal verge

Dentate line

Rectum

Sigmoid colon

Rectosigmoid junction

Peritoneal reflection

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Peritoneum: serous membrane lining the interior of the abdominal cavity and covers the abdominal organs.

Rectum is “extraperitoneal” Rectum lies below the peritoneal reflection and outside of peritoneal cavity

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GreaterOmentum

GreaterOmentum

Liver StomachVessels

Gallbladder

Ligament

slide 9

GreaterOmentum

Transversecolon

coils ofjejunum

Descendingcolon

Ascendingcolon

Appendix

Cecum coils of ileum

Greater Omentum:(reflected upward)

slide 107

Mesentery (Mesenteries): folds of peritoneum- these attach the colon to the posterior abdominal wall.

Visceral peritoneum: = Serosa covering of colon (organs)

Parietal peritoneum: = Serosa covering of ABD cavity (body cavities) 8

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Colon & Rectum Wall Anatomy

Mucosa

Subserosa

Muscularis propria

Submucosa

Serosa

Lumen

Peritoneum 9

(Lumen of Colon)

MUCOSA

SUBMUCOSA

MUSCULARISPROPRIA

SUBSEROSALFAT

SEROSA(Visceral Peritoneum)

epithelium

laminapropria

muscularismucosa

circular

longitudinal

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Layers of Colon Wall

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EOD Tumor

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Code 300• Invasion thru muscularis propria• Subserosal tissue/subserosal fat invaded

• Non‐peritonealizedpericolic/perirectal tissues invaded:• POSTERIOR SURFACE of:

• Ascending colon• Descending colon• Hepatic flexure• Splenic flexure

• MIDDLE 1/3 of Rectum• Anterior surface

• LOWER 1/3 of Rectum

Code 400• Mesentery• Pericolic/perirectal fat

• Peritonealized pericolic/perirectal tissues invaded:• ANTERIOR/Lateral surfaces of:

• Ascending colon• Descending colon• Hepatic flexure• Splenic flexure

• Cecum• Sigmoid Colon• Transverse Colon• Rectosigmoid• Rectum middle 1/3 

• Anterior surface

Types of Polyps I

Source: Abeloff et al: Clinical Oncology, third edition, Elsevier Churchill Livingstone, 2004

Pedunculated(on a stalk)

Sessile(flat)

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Types of Polyps IITubular Tubulovillous Villous

StalkMuscularis

mucosaSubmucosaMuscularis

propria

Head

Source: A.T. Skarin, Atlas of Diagnostic Oncology, 2nd ed., Mosby Wolfe, 1996

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Lymph NodesLymph Nodes named after

artery and veins

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Colorectal Anatomy

J

E

Match Terms below to Letters,(a letter maybe used more than once)

Appendix ____Anus ____Ascending Colon ____Cecum ____Descending Colon ____Hepatic Flexure ____Ileum ____ Left colon ___Rectum ____Rectosigmoid ____Right colon ____Sigmoid ____Splenic Flexure ____Transverse colon ____

Place an X on the spot to represent the Ileocecalvalve/junction.

A

BC

D

F

G

KL

H

I

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Colorectal Anatomy

J

E

Match Terms below to Letters,(a letter maybe used more than once)

Appendix __B__Anus _L___Ascending Colon __D__Cecum __C__Descending Colon __H__Hepatic Flexure __E__Ileum __A__ Left colon __H_Rectum _K___Rectosigmoid ___J_Right colon _D___Sigmoid __I__Splenic Flexure __G__Transverse colon __F__

Place an X on the spot to represent the Ileocecalvalve/junction.

A

BC

D

F

G

KL

H

I

X

RIGHT LEFT

Colorectal Anatomy

J

E

Match Terms below to Letters,(a letter maybe used more than once)

Appendix __B__Anus _L___Ascending Colon __D__Cecum __C__Descending Colon __H__Hepatic Flexure __E__Ileum __A__ Left colon __H_Rectum _K___Rectosigmoid ___J_Right colon _D___Sigmoid __I__Splenic Flexure __G__Transverse colon __F__

Place an X on the spot to represent the Ileocecalvalve/junction.

A

BC

D

F

G

KL

H

I

X

Which is the Distal end of the large bowel?

Which is the Proximalend?

If surgery removed a segment of colon, from the ascending colon to mid-transverse colon; which end of the surgical specimen is the distalend? D or F ?This relates to surgical margins: D is the ______margin F is the ______ margin

Colon surgery: segment H to J is removed. What is the Distal and Proximal margins?

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A

D

C

B

E

Lumen

Peritoneum

Colon & Rectum Wall Anatomy

Mucosa ___Muscularis propria ____Serosa ____Submucosa ____Subserosa ____

WHAT is “outside” the Serosa layer?

Colon & Rectum Wall Anatomy

A

D

C

B

E

Lumen

Peritoneum

Mucosa _A__Muscularis propria _C___Serosa _E___Submucosa __B__Subserosa __D__

Staging of colon cancer is based on spread of cancer from lumen through the bowel wall

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Questions?Contact InfoLori Somers, RNTraining & Quality ImprovementState Health Registry of Iowalori-somers@uiowa.edu

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